trans fat

What the deuce is trans fat, and why do I care that apparently everything I eat has zero grams of it?

I bought some groceries, and I don't think I could pick up a single thing that didn't jump out and scream "Zero Grams Trans Fat!"

Well... they didn't SCREAM scream... you know... just visually "scream". Obviously, a can of Pringles can't scream. But if they could, I bet they'd mention SOMETHING about how they completely lack any trans fat (which I'm sure is bad for me even though no one knew what it was a year ago).

I guess I'll try to avoid it, since I reckon I don't need much more fat (in any form), but from the looks of this Pringles can... maybe the trans fat is trying to avoid ME...